Insulin and Glucagon

What is Insulin and Glucagon?

The human body needs blood glucose i.e blood sugar in required amounts for function and proper metabolism of body. Body takes carbohydrates from food and converts them into glucose i.e a simple form of sugar and this sugar plays a very vital source of energy in the body. Body blood sugar level measures how effectively our body is using glucose. Both insulin and glucagon hormone maintain this glucose level in the body, they are secreted by pancreas and thus referred to as pancreatic endocrine hormones. In case the body is not able to convert enough glucose, blood sugar levels remain high. Insulin helps the cell absorb glucose and reduces blood glucose level by providing glucose to the body. But in case if blood sugar levels are low, then the pancreas releases glucagon. Glucagon commands the liver to release stored glucose, which causes an increase in blood sugar level. 


Insulin Secretory Pathway:

Insulin secretion is a process in the human body that gives response when blood glucose levels in the blood increases.It is known that insulin facilitates the entry of glucose into the cells. The pancreatic b cells act as a self-contained system to secrete insulin in response to changes in level of blood glucose concentration, in order to maintain glucose homeostasis inside the body. The normal fasting blood sugar/glucose level in the human body is between 80mg/100mL and 90mg/100mL. This leads to a decrease in level of insulin. Insulin is produced in the pancreas and is synthesized in the pancreas within the beta cells i.e b-cells of the islets of Langerhans.


Function of Insulin Hormone:

Insulin plays very crucial role in various functioning of the body and they are:

  1. They maintain the level of glycogen synthesis.

  2. They maintain a level of lipid synthesis inside the body.

  3. They also play a crucial role during the esterification process of fatty acid.

  4. Insulin regulates how the body uses and stores glucose and fat present in the body.

  5. Insulin maintains blood glucose levels by instructing the liver and muscle and fat cells to take in glucose from the blood.

  6. Increase or decrease in concentration of insulin leads to secretion of hydrochloric acid by parietal cells in the stomach.


Glucagon Secretory Pathway:

Glucagon is a type of peptide hormone, produced by alpha cells of the pancreas. It works to raise the concentration of glucose  and fatty acid  in the bloodstream, and is considered to be the main catabolic hormone of the body. It is also used as a medication to treat a number of health conditions. Its function is opposite to that of insulin, which lowers extracellular glucose level in the body.  It is produced from proglucagon, encoded by the GCG gene. The pancreas another function is to  release glucagon when the amount of glucose in the bloodstream is too low i.e if blood glucose level decreases. Glucagon causes the liver  to participate in glycogenolysis: it is a process of converting stored glycogen into glucose, which is further released into the bloodstream. High blood-glucose levels, on the other hand, stimulate the release of insulin into the bloodstream. Insulin allows glucose to be taken up and used by insulin-dependent tissues present in the body.


Function of Glucagon:

Glucagon plays active role in body during various metabolic activities, they are:

  1.  They instruct the liver to break down glycogen to be released into the blood as glucose

  2. They help in activating gluconeogenesis process i.e the process of conversion of amino acids into glucose

  3. They also break down stored fat triglycerides into fatty acids for use as fuel by cells for performing various metabolic activities.


Broken Balance:

Regulating the body’s blood sugar requirements is quite a feat; however, when this balance isdisturbed, certain metabolic and physical disorders arise. These include type 1 and type 2 diabetes. When the body starts producing too much insulin, the cells stop absorbing too much glucose. Which leads the liver to produce too little glucose. This condition leads to a condition called hypoglycemia, where blood sugar levels are dangerously low.

On the other hand, too little insulin can lead to a condition called hyperglycemia, which is characterised by high blood sugar. If this problem is not treated, it can lead to a potentially dangerous condition known as diabetic coma.


MCQ Based on Insulin and Glucagon:


1. Which Cell of Pancreas Produces Insulin Hormone:

  1. Alpha-cells

  2. Beta-cell

  3. Gyma-cell

Answer: (b)


2. Which Cell of Pancreas Produce Glucagon Hormone:

  1. Alpha-cell 

  2. Beta-cell

  3. Gymsa-cell

Answer: (a) 


3. Normal Blood Glucose Level of Human Body is:

  1. 80mg/100ml

  2. 100mg/120ml

  3. 120mg/1150ml

Answer: (a)


4. Insulin is produced in response to following reason:

  1. Increased blood sugar

  2. Decreased blood sugar

  3. Normal blood sugar

Answer: (a)

FAQ (Frequently Asked Questions)

1. Difference Between Insulin and Glucagon?

Insulin 

Glucagon

1. Insulin is a hormone that is produced by the beta cells of the Islets of Langerhans of the pancreas.

1. Glucagon hormone is produced by alpha cells of the Islets of Langerhans of the pancreas.

2. It is produced in response to high blood sugar.

2. It is produced in response to low blood sugar level.

2. Role of Insulin in the Human Body?

Insulin helps control blood glucose/sugar levels by instructing the liver, muscle and fat cells to take in glucose from the blood. It therefore helps cells to take in glucose to be used for energy. If the body has sufficient energy, insulin signals the liver to take up glucose and store it as glycogen.

3. Role of Glucagon in the Body?

Glucagon's role in the body is to prevent blood glucose levels from decreasing too low. To do this, it acts on the liver in various ways: It stimulates the conversion of stored glycogen which is stored in the liver to glucose, which can be released into the bloodstream. This process is called glycogenolysis.

4. What is Insulin and Glucagon?

Body takes carbohydrates from food and converts them into glucose i.e a simple form of sugar and this sugar plays a very vital source of energy in the body. Body blood sugar level measures how effectively our body is using glucose. Both insulin and glucagon hormone maintain this glucose level in the body, they are secreted by pancreas and thus referred to as pancreatic endocrine hormones.